1. Field of the Invention
The present invention relates to a working 4-cycle engine for use as a power source for a rammer, trimmer or the like, and particularly, to a working 4-cycle engine including a cylinder block which is connected to a crankcase having an oil pan in a lower portion thereof. The cylinder block is inclined sideways with respect to the crankcase.
2. Description of the Related Art
Conventionally, a 2-cycle engine which does not require an oil pan has been widely used as a working engine.
Even in the working engine, however, the employment of a 4-cycle engine is necessary from the viewpoint of purification of an exhaust gas. The present applicant has already proposed a 4-cycle engine of the above-described construction (see Japanese Patent Application No. 7-87620).
In the 4-cycle engine of the above-described construction, if this engine remains tilted for a long time in the direction of inclination of the cylinder block, there is a possibility that oil flowing from the oil pan into a cylinder in the cylinder block, may flow through the contact of a piston ring and cylinder block wall into a combustion chamber.